In a certain plate material stocker facility that stores raw plate materials carried into a plate material processing machine and product plate materials carried out from the plate material processing machine, a plurality of shelves are provided which are arranged in stages and on which pal lets with the plate materials stacked thereon are stored. In a plate material stocker facility of this kind, an elevator device loads and unloads the pallets onto and from the respective shelves (for example, the Unexamined Japanese Patent Application Publication (Tokkai-Hei) No. 5-85608). A plate material conveying device (for example, the Unexamined Japanese Patent Application Publication (Tokkai-Hei) No. 2000-117374) conveys the plate materials between the plate material processing machine and the pallets in the plate material stocker facility.
The conventional plate material stocker facility has the elevator device and a device that transfers the pallets between the elevator device and the shelves or the plate material conveying device. The conventional plate material stocker facility thus has a complicated structure. Furthermore, a power source is required to drive the above-described devices. Moreover, because of the heavy weight of the pallet, the elevating and lowering speed of the elevator cannot be significantly increased. A long time is also required to transfer the pallets between the elevator device and the shelves or the plate material conveying device. It is thus difficult to improve the efficiency with which the pallets are loaded in and unloaded from the plate material stocker facility.
To solve this problem, a plate material stocker facility may be provided in which the plate material conveying device includes a slider that is movable in a horizontal direction to draw out a pallet from any of a plurality of pallet support portions of the plate material stocker facility. In this case, the slider includes a draw-out tool that moves in a draw-out direction to draw out a pallet from any of the pallet support portions.
However, the plurality of pallet support portions are supported by, for example, four posts arranged in the respective corners of the pallet support portions. Thus, when the slider moves forward to or backward from the pallet support portions, the draw-out tool needs to move around the posts. The draw-out tool thus has a complicated structure.